Adds http support to node_stream logic

src/display/network.js

@@ -14,9 +14,10 @@
  */
 
 import {
-  assert, createPromiseCapability, globalScope, isInt, MissingPDFException,
+  assert, createPromiseCapability, globalScope, MissingPDFException,
   UnexpectedResponseException
 } from '../shared/util';
+import { validateRangeRequestCapabilities } from './network_utils';
 
 if (typeof PDFJSDev !== 'undefined' && PDFJSDev.test('FIREFOX || MOZCENTRAL')) {
   throw new Error('Module "./network" shall not ' +
@@ -350,51 +351,27 @@ function PDFNetworkStreamFullRequestReader(manager, options) {
 }
 
 PDFNetworkStreamFullRequestReader.prototype = {
-  _validateRangeRequestCapabilities: function
-      PDFNetworkStreamFullRequestReader_validateRangeRequestCapabilities() {
+  getResponseHeader(name) {
+    let fullRequestXhrId = this._fullRequestId;
+    let fullRequestXhr = this._manager.getRequestXhr(fullRequestXhrId);
 
-    if (this._disableRange) {
-      return false;
-    }
-
-    var networkManager = this._manager;
-    if (!networkManager.isHttp) {
-      return false;
-    }
-    var fullRequestXhrId = this._fullRequestId;
-    var fullRequestXhr = networkManager.getRequestXhr(fullRequestXhrId);
-    if (fullRequestXhr.getResponseHeader('Accept-Ranges') !== 'bytes') {
-      return false;
-    }
-
-    var contentEncoding =
-      fullRequestXhr.getResponseHeader('Content-Encoding') || 'identity';
-    if (contentEncoding !== 'identity') {
-      return false;
-    }
-
-    var length = fullRequestXhr.getResponseHeader('Content-Length');
-    length = parseInt(length, 10);
-    if (!isInt(length)) {
-      return false;
-    }
-
-    this._contentLength = length; // setting right content length
-
-    if (length <= 2 * this._rangeChunkSize) {
-      // The file size is smaller than the size of two chunks, so it does
-      // not make any sense to abort the request and retry with a range
-      // request.
-      return false;
-    }
-
-    return true;
+    return fullRequestXhr.getResponseHeader(name);
   },
 
   _onHeadersReceived:
       function PDFNetworkStreamFullRequestReader_onHeadersReceived() {
+    let { allowRangeRequests, suggestedLength, } =
+      validateRangeRequestCapabilities({
+        getResponseHeader: this.getResponseHeader.bind(this),
+        isHttp: this._manager.isHttp,
+        rangeChunkSize: this._rangeChunkSize,
+        disableRange: this._disableRange,
+      });
+
+    // Setting right content length.
+    this._contentLength = suggestedLength || this._contentLength;
 
-    if (this._validateRangeRequestCapabilities()) {
+    if (allowRangeRequests) {
       this._isRangeSupported = true;
     }
 

src/display/network_utils.js

@@ -0,0 +1,56 @@
+/* Copyright 2012 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { isInt } from '../shared/util';
+
+function validateRangeRequestCapabilities({ getResponseHeader, isHttp,
+                                            rangeChunkSize, disableRange, }) {
+  let returnValues = {
+    allowRangeRequests: false,
+    suggestedLength: undefined,
+  };
+  if (disableRange || !isHttp) {
+    return returnValues;
+  }
+  if (getResponseHeader('Accept-Ranges') !== 'bytes') {
+    return returnValues;
+  }
+
+  let contentEncoding = getResponseHeader('Content-Encoding') || 'identity';
+  if (contentEncoding !== 'identity') {
+    return returnValues;
+  }
+
+  let length = getResponseHeader('Content-Length');
+  length = parseInt(length, 10);
+  if (!isInt(length)) {
+    return returnValues;
+  }
+
+  returnValues.suggestedLength = length;
+  if (length <= 2 * rangeChunkSize) {
+    // The file size is smaller than the size of two chunks, so it does
+    // not make any sense to abort the request and retry with a range
+    // request.
+    return returnValues;
+  }
+
+  returnValues.allowRangeRequests = true;
+  return returnValues;
+}
+
+export {
+  validateRangeRequestCapabilities,
+};